All about DNG files

DNG stands for Digital Negative and is an open RAW format released by Adobe on 27 September 2004. I think the name (much like ‘RAW’) explains very well what the files contain: the unaltered(*) raw data of the photograph – essentially a digital negative. Since the iPhone 12 Pro and 12 Pro Max, Apple has also been using the format.^[1]

As we know today, Adobe did not achieve its original goal of establishing a uniform raw format for all manufacturers. Almost every major manufacturer has established its own format. Unlike most proprietary formats from other manufacturers (such as CR2, NEF or ARW), the DNG specification is publicly documented and Adobe grants licence-free use, provided the implementation complies with the specification.^[2] The Library of Congress recommends DNG as an archiving format for photographs (to ensure long-term readability).^[3]

Versions and development

Apple ProRAW

With iOS 14.3, Apple introduced the ProRAW format in December 2020 (finalised in 2021). The format is technically based on DNG 1.6 and combines the raw data from iPhone cameras with Apple’s image processing (such as Deep Fusion and Smart HDR). Everything is saved as 12-bit linear DNG in files ranging from approx. 25 MB (12 MP) to 75 MB (48 MP).

Cameras with native DNG support

Some manufacturers offer native DNG support: Leica (since the Digital Module-R in 2005), Hasselblad, Pentax, Ricoh and Casio on selected models. Drones from DJI and Yuneec, as well as various Android smartphones, also save directly in the open DNG format. For maximum flexibility and archiving, the open DNG format is a strong selling point.

Technical basis: TIFF 6.0 and TIFF-EP

Technically, DNG is based on an extension of the TIFF 6.0 format and is compatible with the TIFF-EP standard (ISO 12234-2). TIFF-EP was defined in 2001 specifically for digital cameras and specifies how raw data from camera sensors is structured and stored – including information about the sensor’s Bayer matrix. DNG extends this standard with additional tags for lens corrections, colour profiles and camera calibration. Metadata (EXIF, IPTC, XMP) is stored directly within the file; separate sidecar files (files stored alongside the image that contain the metadata) are not required.

(*) Since DNG 1.4, images can also be compressed with loss, in which case the data is no longer unaltered.

Sources

[1] support.apple.com – About Apple ProRAW
[2] helpx.adobe.com – Digital Negative (DNG)
[3] loc.gov – Adobe Digital Negative (DNG)

Last updated on 19. March 2026 by Sören with the experience of more than 128,215,205 converted files since 2013.